Philips LC4.5E Service Manual Download

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Circuit Descriptions, Abbreviation List, and IC Data Sheets

EN 67

LC4.5E AA

9.7.1

Features

The Scaler provides several key IC functions:
•

Scaling.

•

Auto-configuration/ Auto-Detection.

•

Various Input Ports:
–

Analog RGB.

–

Video Graphics.

•

Integrated LVDS Transmitter.

•

On-chip Micro-controller

9.7.2

Inputs

Analog RGB

The RGB input is fed to pins B2, C2 and D2. This input consists
of either the Hercules RGB output or the RGB/YPbPr input of
the VGA connector. The Scaler can switch between the two
signals via the PC_HD_SEL signal and selection IC SM5301.

PC (VGA) Input

The VGA input is processed by the VGA block of the Scaler.
The Scaler supports pixel frequencies up to 165 MHz.
YPbPr format is also supported via the VGA interface and
covers a resolution of 480p/560p/720p/1080i.

9.7.3

Output

The Display Output Port provides data and control signals that
permit the Scaler to connect to a variety of display devices
using a TTL or LVDS interface. The output interface is
configurable for single or dual wide TTL/LVDS in 18, 24 or 30-
bit RGB pixels format. All display data and timing signals are
synchronous with the DCLK output clock. The integrated LVDS
transmitter is programmable to allow the data and control
signals to be mapped into any sequence depending on the
specified receiver format.

9.8

Audio Processing

Figure 9-4 Block diagram audio processing

The audio decoding is done entirely via the Hercules. The IF
output from the Tuner is fed directly to either the Video-IF or the
Sound-IF input depending on the type of concept chosen.
There are mainly two types of decoder in the Hercules, an
analogue decoder that decodes only Mono, regardless of any
standards, and a digital decoder (or DEMDEC) that can decode
both Mono as well as Stereo, again regardless of any
standards.

In this chassis, the analogue decoder is used in two cases:

•

It is used for AM Sound demodulation in the Europe
SECAM LL’ transmission.

•

It is used for all FM demodulation in AV-Stereo sets.

9.8.1

Diversity

The diversity for the Audio decoding can be broken up into two
main concepts:
•

The Quasi Split Sound concept used in Europe and some
AP sets.

•

The Inter Carrier concept, used in NAFTA and LATAM.

The UOC-III family makes no difference any more between
QSS- and Intercarrier IF, nearly all types are software-
switchable between the two SAW-filter constructions.

Simple data settings are required for the set to determine
whether it is using the Inter Carrier or the QSS concept. These
settings are done via the “QSS” and “FMI” bit found in SAM
mode. Due to the diversity involved, the data for the 2 bits are
being placed in the NVM location and it is required to write once
during start-up.

On top of that, it can be further broken down into various
systems depending on the region. The systems or region
chosen, will in turn affect the type of sound standard that is/are
allowed to be decoded.
•

For the case of Europe, the standard consists of BG/DK/I/
LL’ for a Multi-System set. There are also versions of
Eastern Europe and Western Europe set and the standard
for decoding will be BG/DK and I/DK respectively. FM
Radio is a feature diversity for the Europe sets. The same
version can have either FM Radio or not, independent of
the system (e.g. sets with BG/DK/I/LL’ can have or not
have FM radio).

•

For the case of NAFTA and LATAM, there is only one
transmission standard, which is the M standard. The
diversity then will be based on whether it has a dBx noise
reduction or a Non-dBx (no dBx noise reduction).

•

For the case of AP, the standard consists of BG/DK/I/M for
a Multi-System set. The diversity here will then depend on
the region. AP China can have a Multi-System and an I/DK
version. For India, it might only be BG standard.

9.8.2

Functionality

The features available in the Hercules are as follows:
•

Treble and Bass Control.

•

Surround Sound Effect that includes:
–

Incredible Stereo.

–

Incredible Mono.

–

3D Sound (not for AV Stereo).

–

TruSurround (not for AV Stereo).

–

Virtual Dolby Surround, VDS422 (not for AV Stereo).

–

Virtual Dolby Surround, VDS423 (not for AV Stereo).

–

Dolby Pro-Logic (not for AV Stereo).

•

Bass Feature that includes:
–

Dynamic Ultra-Bass.

–

Dynamic Bass Enhancement.

–

BBE (not for AV Stereo).

•

Auto-Volume Leveller.

•

5 Band Equalizer.

•

Loudness Control.

All the features stated are available for the Full Stereo versions
and limited features for the AV Stereo

9.8.3

Audio Amplifier

The audio amplifier part is very straightforward. It uses the
integrated power amplifier TDA7297D, and delivers a
maximum output of 2 x 15 W

RMS

The maximum operating condition for this amplifier is 20 V
unloaded. Normal operating supply is from 6.5 V to 18 V.
Muting is done via the SOUND_ENABLE line connected to pin
13 of the amplifier-IC and coming from the Hercules.

Side in

All region

SCART1 out

Europe only

SCART2 out

*Europe only

Monitor out

* Not available

SCART2 in

*Europe only

AV2 in

AP/USA/Latam